As mobile computing devices (smart phones, tablets, wearable computers, and the like) have increased in number and capability, the devices have become increasingly useful for the storage of private data signatures. However, the varying capabilities of mobile devices can make use of such devices challenging when implementing security solutions. Users have different devices, and depending on the device capabilities, the mobile devices have different levels of security. Some advanced mobile devices have specialized hardware and software to enable improved security; however, depending on such features alienates less capable devices and limits the scale at which secure practices can be implemented. In one instance, Google Wallet uses a security element to store credit card credentials. But because the security element is only implemented on a limited number of devices, such a financial mechanism is limited to only capable devices. Thus, there is a need in the digital signature field to create new and useful system and methods for opportunistic cryptographic key management on an electronic device. This invention provides such a new and useful system and methods.